Networks are continuing to grow, with current and projected rates in excess of 30% annualized increase in bandwidth. Such growth rates imply network bandwidth doubling approximately every two-and-a-half years. At the same time, network hardware cost, space, and power consumption allocations are staying roughly flat. Equipment manufacturers must therefore deliver substantial continuous reductions in per-bit metrics related to cost, space, and power. Telecommunication, data communication, high-performance computing, and the like systems are typically deployed in physical hardware shelves that are mounted in racks or frames. For example, typical racks or frames are either 19, ˜21, or 23 inches in practice. A rack unit (abbreviated as U or RU) is a unit of measure describing the height of equipment intended for mounting in a rack or frame, e.g. one RU equals 1.75 inches (44.45 mm) in height. Various standards associated with racks or frames are described by Telecordia's GR-63-CORE, “NEBS Requirements: Physical Protection” (04/2012), European Telecoms Standards Institute (ETSI), American National Standard Institute (ANSI), etc.
A conventional system includes a number of vertically arranged cards that are inserted into a backplane in a physical shelf mounted to a rack (e.g., 19″, ETSI, or 21″ rack). A conventional system may also include a combination of vertically arranged cards and horizontally arranged cards inserted into a backplane and/or midplane. Note, cards can also be interchangeably referred to as modules, blades, circuit packs, etc. Generally, in networking systems, cards can be further divided into functionality with cards either being line cards and/or switch cards. The line cards provide input/output (I/O) to the shelf and typically include a plurality of physical media devices such as optical transceivers, etc. on a front of the cards. The line cards can be referred to as I/O cards, interface cards, ingress/egress devices, and the like. The switch cards (which can also be referred to as fabrics or switch fabric cards) provide electrical and/or optical switching functionality and/or other processing functionality and typically do not include physical I/O ports on a front of the cards.
What is needed is a shelf and system that preserves compliance to various specifications (e.g., NEBS), conforms to service provider operational requirements, supports high density card deployment, and the like.